What is Duplex Steel?

Many materials have been developed to have specific properties that work for particular applications. Duplex steel is a good example of this, and is steel which has been enhanced with chromium that gives it effective resistance against corrosion. As well as corrosion resistance, Duplex also has several other benefits, which makes it one of the most valued materials across a range of industries, especially the chemical industries.

At certain temperatures, Duplex is considered to have high toughness and good ductility. Essentially, ductility is a material’s propensity to deform under tensile stress.
Whilst at higher temperatures duplex is known to become brittle, at lower temps it’s extremely tough. It is also considered to be about twice as strong as ferritic steels.

Duplex, and Super Duplex to an even greater extent, is extremely resistant to corrosion. It’s used widely in the chemical industry, for instance in the construction of piping. Specifically, it offers a high level of resistance to chemical corrosion such as sulphide or chloride corrosion.

The specific applications of Duplex are numerous: It is used extensively in piping, for instance a seamless steel tube or seamless stainless steel pipe, especially for pipes that have to transport corrosive materials such as seawater or chemicals. It’s resistance to corrosion means that it’s also used very effectively for the construction of storage tanks.

Duplex comes in different grades, i.e. Duplex and Super Duplex, with Super Duplex being even more corrosion resistance and durable than Duplex.